WEBVTT - Licking, Part 2 0:00:03.040 --> 0:00:06.800 Welcome to Stuff to Blow Your Mind production of iHeartRadio. 0:00:12.600 --> 0:00:14.480 Hey you welcome to Stuff to Blow Your Mind. My 0:00:14.560 --> 0:00:15.840 name is Robert Lamb. 0:00:15.920 --> 0:00:18.439 And I am Joe McCormick, and we're back with part 0:00:18.440 --> 0:00:21.159 two in our series on the theme of licking with 0:00:21.440 --> 0:00:24.920 the tongue. In part one of this series, we talked 0:00:24.920 --> 0:00:28.400 about the role of licking in ancient Egyptian magic, which 0:00:28.640 --> 0:00:32.000 spans everything from the blessed licks and laps of the 0:00:32.040 --> 0:00:36.320 cow goddess Hathor to the sorceress violence of the crocodile 0:00:36.360 --> 0:00:39.760 who licks off the protective spells of the dead, and 0:00:39.840 --> 0:00:42.880 that discussion led to some diversions to talk about things 0:00:42.920 --> 0:00:46.080 like the adaptive function of the snake's forked tongue licking 0:00:46.120 --> 0:00:49.879 the air and the role that plays in chemo sensation 0:00:50.520 --> 0:00:54.560 and research about when children acquire a disgust reaction to 0:00:54.720 --> 0:00:58.800 contamination of food surfaces by licking. After that, we took 0:00:58.800 --> 0:01:02.040 a hard pivot into candyland and talked about the frankly 0:01:02.120 --> 0:01:04.559 shocking amount of research that has gone into the question 0:01:04.680 --> 0:01:06.920 how many licks does it take to get to the 0:01:06.959 --> 0:01:09.679 center of a tutsi pop, which is a deep rabbit 0:01:09.720 --> 0:01:13.160 hole that becomes more philosophically interesting that the longer you 0:01:13.200 --> 0:01:14.000 gaze into it. 0:01:14.640 --> 0:01:17.800 Yeah, I keep thinking about those TUTSI roll experiments. I 0:01:17.800 --> 0:01:20.760 think pretty much most, if not all of them were 0:01:20.800 --> 0:01:22.840 I think, at least on some level and in some 0:01:22.920 --> 0:01:27.680 phase approached with a fair amount of wit and whimsy. 0:01:28.120 --> 0:01:31.240 But you get the sense that like, once these scientific 0:01:31.319 --> 0:01:34.480 minds started digging into it, like it just becomes irresistible. 0:01:34.520 --> 0:01:37.640 It's just you've got to follow it through and put 0:01:37.640 --> 0:01:38.160 in the work. 0:01:39.000 --> 0:01:42.240 So we're back today to talk about licking some more. 0:01:43.160 --> 0:01:46.240 And I promised that in today's episode we would talk 0:01:46.280 --> 0:01:49.840 about wound licking behavior in animals, So I think that's 0:01:49.880 --> 0:01:52.320 where we want to start. First of all, just Rob, 0:01:52.360 --> 0:01:54.520 I've got a few photos for you to look at 0:01:54.560 --> 0:01:58.520 in the outline here that are various statues of a 0:01:58.600 --> 0:02:02.680 Catholic saint. No as I'm a little confused about how 0:02:02.680 --> 0:02:05.360 to pronounce this guy's name because it's spelled different ways 0:02:05.360 --> 0:02:09.360 in different languages. I believe it's Saint Roche or Saint Rock, 0:02:09.520 --> 0:02:12.639 sometimes spelled r o c h, sometimes spelled r c 0:02:12.880 --> 0:02:19.320 K or rck e or rch e anyway, a Catholic 0:02:19.400 --> 0:02:23.840 saint widely associated with hospitals, and with the Black Death. 0:02:24.480 --> 0:02:28.359 I was looking at a gallery page about him and 0:02:28.440 --> 0:02:31.639 some artworks of him from the Met Museum, which are 0:02:31.760 --> 0:02:35.880 talking pointing out that very often depictions of this saint, 0:02:36.600 --> 0:02:40.480 he is shown with his left hand touching a sore 0:02:40.560 --> 0:02:43.600 on his thigh, which that explains why so many of 0:02:43.639 --> 0:02:45.920 the images of this saint he looks like literally like 0:02:45.960 --> 0:02:48.440 he's trying to show a little leg, like he's lifting 0:02:48.480 --> 0:02:50.120 something up. He's like, hey, have a look at my 0:02:50.160 --> 0:02:50.639 thigh here. 0:02:50.960 --> 0:02:53.919 Yeah, in many cases too, or in some depictions it's 0:02:53.960 --> 0:02:56.960 like he's wearing shorts, so with like both legs on 0:02:57.040 --> 0:02:57.680 full display. 0:02:58.200 --> 0:03:01.600 Yeah, into these leggy outfits. Often also he has a 0:03:01.600 --> 0:03:05.440 dog beside him, and both the showing of the sore 0:03:05.680 --> 0:03:07.680 on his leg, there's like a sore on his thigh 0:03:07.720 --> 0:03:10.280 showing this bulge or sore on his thigh and the 0:03:10.280 --> 0:03:13.760 dog beside him connect to this legend about the Saint 0:03:14.200 --> 0:03:17.680 that he at one point was traveling. I think he 0:03:17.760 --> 0:03:21.160 was on a pilgrimage and he became very ill. I 0:03:21.160 --> 0:03:23.440 don't know if he got the plague or some other illness. 0:03:24.080 --> 0:03:27.320 The boil or the bulge would sort of connect to 0:03:27.320 --> 0:03:30.240 the idea that he got bubonic plague. But he fell 0:03:30.400 --> 0:03:34.320 ill and he collapsed somewhere, But then he was miraculously 0:03:34.400 --> 0:03:38.240 healed by a dog, a dog that brought him bread 0:03:38.520 --> 0:03:40.320 and licked his wounds. 0:03:41.040 --> 0:03:43.360 And in fact, in these various depictions you'll see the 0:03:43.400 --> 0:03:47.520 dog either carrying the bread, holding the bread up to 0:03:47.600 --> 0:03:50.360 the man, or sometimes looks like maybe the bread is 0:03:50.720 --> 0:03:53.120 on the ground next to the dog. I guess the 0:03:53.160 --> 0:03:54.920 dog brought it and dropped it like here you go. 0:03:55.840 --> 0:03:58.640 And in fact, this is not even the only major 0:03:58.720 --> 0:04:04.120 figure in Christianity to be part of a dog licking 0:04:04.240 --> 0:04:08.240 sores or dog licking his wounds motif that is said 0:04:08.320 --> 0:04:11.560 about the poor man Lazarus in the story in the Bible. 0:04:11.640 --> 0:04:14.200 Do you remember the rob Oh? Yes, the parable Jesus 0:04:14.200 --> 0:04:17.000 tells like he's ill and he falls down and the 0:04:17.440 --> 0:04:20.280 dogs lick his sores. It always seemed kind of gross. 0:04:21.360 --> 0:04:23.800 And by the way, I just I'll explain more about 0:04:23.839 --> 0:04:26.479 this as we go on in a few minutes here, 0:04:26.520 --> 0:04:28.560 but I want to say at the top, having a 0:04:28.600 --> 0:04:31.359 dog lick your wounds is not a reliable way to 0:04:31.400 --> 0:04:34.720 be healed of illness or to treat injuries. 0:04:35.400 --> 0:04:38.080 Yes, no matter what you might hear on Instagram or 0:04:38.080 --> 0:04:42.440 TikTok about the latest wound healing trend that's sweeping the nation. 0:04:42.640 --> 0:04:46.279 It's all natural, it really is, but there are reasons 0:04:46.480 --> 0:04:50.520 even though it's not actually advisable, there are reasons why 0:04:50.560 --> 0:04:53.400 people get there mentally to think, oh, a dog healed 0:04:53.440 --> 0:04:56.640 me by licking my wounds. So in the last episode 0:04:56.680 --> 0:04:59.960 we talked about the licking of injuries in the Egyptian 0:05:00.040 --> 0:05:03.920 magical context and how that was probably modeled on the 0:05:03.960 --> 0:05:08.160 observation of animals licking their wounds in nature. So I 0:05:08.240 --> 0:05:12.040 was wondering, first of all, which animals do and do 0:05:12.160 --> 0:05:16.000 not lick their wounds. Unfortunately, I don't think I can 0:05:16.120 --> 0:05:20.760 issue any kind of categorical taxonomic statement on this. It's 0:05:20.800 --> 0:05:23.919 not like, oh, mammals do it, and no other animals do. 0:05:24.720 --> 0:05:26.560 The best I can do is offer a kind of 0:05:26.600 --> 0:05:31.120 generalization and incomplete list of animals that have been observed 0:05:31.160 --> 0:05:34.839 licking cuts and punctures in the skin. The behavior does 0:05:34.839 --> 0:05:39.120 seem to be most prevalent in mammals, though not present 0:05:39.279 --> 0:05:43.320 in all mammals and probably not completely limited to them, 0:05:44.400 --> 0:05:48.719 But animals that lick wounds include rodents like mice and rats, 0:05:49.440 --> 0:05:51.440 and a lot of the research on the biology of 0:05:51.480 --> 0:05:54.880 wound licking has been performed in mice and rats. For example, 0:05:54.920 --> 0:05:59.520 there's research showing that in domesticated brown rats, wounds heal 0:05:59.640 --> 0:06:02.760 fast or when the rat is able to reach the 0:06:02.800 --> 0:06:05.680 wound with its mouth to lick it. And this in 0:06:05.720 --> 0:06:09.719 itself kind of highlights some features of wound looking adaptations, 0:06:09.800 --> 0:06:12.560 One that they do seem to help things heal, but 0:06:12.640 --> 0:06:15.920 also that in a lot of animals, self directed licking 0:06:16.040 --> 0:06:18.680 is going to be limited by what parts of the 0:06:18.680 --> 0:06:21.440 body the animal can reach with its own mouth. Some 0:06:21.520 --> 0:06:23.680 animals are more flexible than others. 0:06:23.800 --> 0:06:27.000 Right, right, right, So certainly we think about our own case, 0:06:27.160 --> 0:06:29.440 like we cannot lick every part of our own body 0:06:29.720 --> 0:06:32.280 that we might desire to lick because. 0:06:32.000 --> 0:06:36.240 Of our wound cut on the elbow. You're out of luck. Yeah. Also, 0:06:36.680 --> 0:06:40.880 animals that lick their wounds include many primates humans. Also, 0:06:41.000 --> 0:06:44.120 to some extent, there does appear to be at least 0:06:44.160 --> 0:06:48.240 some latent wound looking instinct in humans, though obviously lots 0:06:48.240 --> 0:06:50.200 of humans don't do it, and there are good reasons 0:06:50.279 --> 0:06:52.480 not to do it if you have other options, which 0:06:52.560 --> 0:06:56.120 most people do, but most I don't know about. Most 0:06:56.200 --> 0:06:59.760 many primates seem to have a wound looking instinct. Monkeys 0:06:59.760 --> 0:07:04.200 and apes or observed to lick wounds in nature. Some carnivores, 0:07:04.279 --> 0:07:07.640 including domestic dogs and cats, lick their wounds. Of course, 0:07:08.600 --> 0:07:14.040 some wild ungulates, such as deer bears lick their wounds. 0:07:14.280 --> 0:07:17.600 Maybe not all bears, but some bears at least. There 0:07:17.640 --> 0:07:21.880 are some reports that horses occasionally lick wounds, but I 0:07:21.920 --> 0:07:23.720 don't know. I was trying to sort this out. Evidence 0:07:23.760 --> 0:07:27.320 on that seems mixed to me. But it's also not 0:07:27.480 --> 0:07:30.720 just mammals, especially if you expand the definition of licking 0:07:30.760 --> 0:07:34.320 a little bit, like I see some reports online of 0:07:35.280 --> 0:07:38.960 anecdotal reports of people who keep reptiles like certain lizards, 0:07:39.000 --> 0:07:42.280 talking about the lizard's licking wounds. But again, the evidence 0:07:42.360 --> 0:07:45.400 is a little fuzzy. In this case, however, there is 0:07:45.560 --> 0:07:51.400 a scientifically recognized behavior in some ant species where injured 0:07:51.600 --> 0:07:54.680 worker ants will be brought back to the colony for 0:07:54.920 --> 0:07:59.720 medical treatment, which essentially amounts to having their wounds licked 0:07:59.800 --> 0:08:03.840 by first aid ants. It's not exactly licking with a 0:08:03.880 --> 0:08:08.880 mammalian tongue, but the wound treating ants will get the 0:08:08.920 --> 0:08:11.200 injured ant, and maybe it's been injured on a raid 0:08:11.240 --> 0:08:14.200 against a bunch of termites, and they'll get the injured 0:08:14.240 --> 0:08:17.640 ant and bring it back and treat the wound site 0:08:17.640 --> 0:08:20.800 by touching it with their mouth parts and applying saliva, 0:08:21.200 --> 0:08:25.200 which helps prevent infection and promotes healing. According to a 0:08:25.240 --> 0:08:29.000 twenty eighteen article by Frank Verhon and Linsen Mayer in 0:08:29.040 --> 0:08:34.320 the species Megaponera analysis, they found that quote lack of treatment. 0:08:34.640 --> 0:08:38.600 Lack of treatment by this licking procedure increased mortality from 0:08:38.640 --> 0:08:42.319 ten percent to eighty percent within twenty four hours, most 0:08:42.480 --> 0:08:45.240 likely due to infections. So being able to get this 0:08:45.400 --> 0:08:48.320 licking treatment from the other ants makes a huge difference 0:08:48.360 --> 0:08:52.200 in survival rates. So if a bunch of animals do 0:08:52.800 --> 0:08:57.200 lick wounds, that raises the question why what are the 0:08:57.200 --> 0:09:01.200 potential benefits of wound licking. It turns out there are 0:09:01.240 --> 0:09:06.440 a bunch first, and I think this one is underappreciated 0:09:06.480 --> 0:09:09.720 in some sources that really focus exclusively on the healing 0:09:09.800 --> 0:09:13.120 properties of saliva. The first thing to mention is the 0:09:13.240 --> 0:09:17.760 mechanical cleaning of the wound area by the tongue. Licking 0:09:17.800 --> 0:09:21.880 the wound can remove necrotic or dead tissue, especially if 0:09:21.880 --> 0:09:25.480 it's only very loosely attached at this point can remove 0:09:25.559 --> 0:09:29.000 dead or dyeing tissue from the wound area. This is 0:09:29.040 --> 0:09:33.800 called dibridement in a surgical context. And licking also, more 0:09:33.840 --> 0:09:39.000 importantly probably removes dirt and other material contaminants from the 0:09:39.120 --> 0:09:42.679 environment from the site of the injury. This is really 0:09:42.760 --> 0:09:47.199 important because dirt and other contaminating solids and some liquids 0:09:47.640 --> 0:09:52.320 are potentially microbial delivery vehicles. They have bacteria and other 0:09:52.400 --> 0:09:55.720 microbes on them and in them. And if say a 0:09:55.720 --> 0:10:00.520 little fleck of soil remains in an open wound, the 0:10:00.640 --> 0:10:04.560 microbes that are densely packed in that soil can move 0:10:04.920 --> 0:10:08.000 from the fleck of soil to the exposed tissue and 0:10:08.040 --> 0:10:11.680 cause an infection. And so licking with the tongue mechanically 0:10:11.800 --> 0:10:14.880 scrapes that fleck of soil out of the wound so 0:10:14.920 --> 0:10:18.160 that it doesn't become a landing craft for a microbial army. 0:10:19.440 --> 0:10:22.040 And note that this is the same reason that doctors 0:10:22.320 --> 0:10:25.079 would advise you to wash a wound as soon as 0:10:25.080 --> 0:10:28.959 possible after you get hurt. Washing a wound out with water, soap, 0:10:29.000 --> 0:10:31.880 and water performs the same function as licking. Here it 0:10:32.000 --> 0:10:35.720 physically removes contaminants that bring a payload of germs with them. 0:10:36.120 --> 0:10:39.440 So basically, whatever is in a dog saliva, there may 0:10:39.520 --> 0:10:43.880 already be things far worse than dog saliva in the wound. Yes, 0:10:44.240 --> 0:10:47.320 so the tongue can just physically remove those again, almost 0:10:47.400 --> 0:10:50.520 like you were rinsing out a wound, which of course 0:10:50.520 --> 0:10:53.960 the dog can't do because it doesn't have access to 0:10:54.440 --> 0:10:56.000 modern medical science and so forth. 0:10:56.160 --> 0:10:59.600 Exactly, Yes, so the dog's tongue, for the dog, is 0:10:59.800 --> 0:11:02.320 the best it can do because it doesn't have clean 0:11:02.400 --> 0:11:07.679 running tapwater. Second, when animals lick a wound, they not 0:11:07.720 --> 0:11:10.400 only get rid of the bad stuff, but they also 0:11:10.840 --> 0:11:15.120 introduce substances to the wound through their saliva that may 0:11:15.200 --> 0:11:20.480 help the wound heal. Some examples here antimicrobial enzymes in 0:11:20.559 --> 0:11:24.960 our saliva that selectively kill germs on contact. A common 0:11:24.960 --> 0:11:29.080 example here is the enzyme lysizyme. This is found in 0:11:29.120 --> 0:11:31.680 a bunch of our body fluids. Actually it's in spit, 0:11:31.840 --> 0:11:36.600 but also tears nasal and epithelial mucus in milk, and 0:11:36.679 --> 0:11:41.160 also in non human body fluids like egg whites. Lysisyme 0:11:41.480 --> 0:11:47.000 selectively attacks GRAM positive bacteria by dissolving their cell walls. 0:11:47.640 --> 0:11:51.640 So if bacteria made horror movies, lysizyme might be a 0:11:51.679 --> 0:11:54.320 good candidate for a melt movie monster. You know, it 0:11:54.440 --> 0:11:56.800 just kind of it melts you. It dissolves your you know, 0:11:56.920 --> 0:12:00.760 the outside of the cells. Another anti my chrobial in 0:12:00.880 --> 0:12:05.720 saliva is called lactoferrin. This is a protein that prevents 0:12:05.760 --> 0:12:10.080 bacteria from growing by starving them of iron. Bacteria need 0:12:10.200 --> 0:12:14.440 iron atoms to reproduce, and lactoferriin bonds to free iron, 0:12:14.520 --> 0:12:17.960 making it unavailable for the bacterial cells. This is called 0:12:18.000 --> 0:12:21.560 iron sequestration. Removes the iron from them and so that 0:12:21.600 --> 0:12:23.720 they can't get what they need in order to grow 0:12:23.720 --> 0:12:27.520 and survive. And that's not even a whole list. Animals 0:12:27.559 --> 0:12:32.480 just have a big host of antibacterial agents in their saliva. 0:12:32.520 --> 0:12:35.800 And note that these antibacterial agents in the saliva wouldn't 0:12:35.840 --> 0:12:41.080 be evolved exclusively for the application to external wounds. They 0:12:41.120 --> 0:12:44.160 play a big role in protecting the body in the mouth, 0:12:44.320 --> 0:12:46.839 like they're doing stuff for your body in your mouth, 0:12:46.920 --> 0:12:50.199 for your digestive system, and for your mouth cavity. Spit 0:12:50.520 --> 0:12:54.040 also contains things that are not just antimicrobials, but things 0:12:54.080 --> 0:12:57.400 that can actively speed up the healing process in the 0:12:57.400 --> 0:13:02.520 affected tissue. And this includes his statins. These are proteins 0:13:02.559 --> 0:13:06.000 that also have antimicrobial properties, but in addition to that, 0:13:06.040 --> 0:13:11.920 they promote healing by causing what's called epithelial migration. They 0:13:11.920 --> 0:13:16.200 cause epithelial cells to migrate to the exposed tissue surface 0:13:16.320 --> 0:13:20.240 and close the wound. And saliva also has growth factor 0:13:20.280 --> 0:13:24.680 proteins like epithelial growth factor and nerve growth factor, and 0:13:24.760 --> 0:13:27.160 you can see some of these influences at work. Actually, 0:13:27.200 --> 0:13:30.520 if you have ever noticed that injuries inside your mouth 0:13:30.760 --> 0:13:33.840 tend to heal a good bit faster than injuries on 0:13:33.880 --> 0:13:35.000 your outer skin. 0:13:35.760 --> 0:13:38.079 Hmmm, I mean that that can be a kind of 0:13:38.120 --> 0:13:41.640 a paradox to consider because sometimes wounds inside your mouth 0:13:42.120 --> 0:13:45.800 are a little more irritating then wounds on your outer skin, 0:13:46.360 --> 0:13:48.680 so they might feel like they hang around longer. So 0:13:48.800 --> 0:13:52.079 I don't know, I'll have to really calculate on this one. 0:13:52.200 --> 0:13:54.880 Well, they might actually hang around longer, depending on things 0:13:54.880 --> 0:13:57.360 like if you keep if something keeps irritating them or 0:13:57.440 --> 0:13:58.439 keeps reopening the. 0:13:58.360 --> 0:14:01.760 Wound a sharp the wheat, then yes, yeah, if. 0:14:01.640 --> 0:14:04.319 You keep cutting it open over and over, like, because 0:14:04.360 --> 0:14:06.680 you're using your mouth in a way that like you know, 0:14:06.760 --> 0:14:09.040 you could actually just keep stuff away from a cut 0:14:09.080 --> 0:14:11.200 on your skin, so there could be ways that something 0:14:11.200 --> 0:14:14.600 in your mouth would last longer, but it is typically 0:14:14.640 --> 0:14:18.520 the case that abrasions and cuts on the oral mucosa 0:14:18.679 --> 0:14:21.160 heal faster than on the outside of the body. And 0:14:21.280 --> 0:14:24.160 one reason for this not the only reason, probably, but 0:14:24.200 --> 0:14:27.760 one reason is the presence of these healing factors and 0:14:27.800 --> 0:14:41.840 antimicrobial agents within the saliva, so a lot of benefits 0:14:41.960 --> 0:14:45.680 in spit. Spit could do a lot for an open wound, 0:14:46.200 --> 0:14:49.960 but these benefits do not come free. Wound looking, in fact, 0:14:50.080 --> 0:14:53.840 has a very high cost. It comes with risks. At 0:14:53.840 --> 0:14:58.160 the same time that it removes contaminants, provides antimicrobial enzymes, 0:14:58.200 --> 0:15:02.760 and stimulates healing, it also so introduces problems of its own. 0:15:03.400 --> 0:15:07.920 For example, failure to regulate the wound looking behavior can 0:15:08.040 --> 0:15:12.360 lead to overlocking, which itself almost creates new wounds or 0:15:12.400 --> 0:15:14.680 makes the wound worse kind of keeps it from healing. 0:15:15.240 --> 0:15:19.240 It can irritate or further injure the skin. A common 0:15:19.240 --> 0:15:22.200 example is that you know a dog just it has 0:15:22.280 --> 0:15:25.360 a wound looking instinct, but it can't turn the instinct off, 0:15:25.400 --> 0:15:28.680 so it just keeps licking a wound, making it actually 0:15:28.760 --> 0:15:30.840 worse and worse, So the injured dog will need a 0:15:30.880 --> 0:15:32.880 cone because it doesn't know when to stop. 0:15:33.480 --> 0:15:35.760 Okay, so that sometimes the cone is for that, I know. 0:15:35.840 --> 0:15:38.000 Sometimes a cone with an animal is also to keep 0:15:38.000 --> 0:15:41.560 them from licking off a medication, which of course they 0:15:41.600 --> 0:15:47.280 have not evolved to understand. Like for the natural world dog, 0:15:47.600 --> 0:15:50.920 the best medicine is the dog saliva. The idea that 0:15:50.960 --> 0:15:53.160 there is a better medicine out there that did not 0:15:53.240 --> 0:15:57.360 come from their mouth is an impossible idea. 0:15:57.840 --> 0:16:00.600 Right, So there can be multiple reasons for I mean, 0:16:00.640 --> 0:16:04.000 it can ye keep a dog from removing medication, can 0:16:04.080 --> 0:16:07.480 keep a dog from tearing out stitches, and can also 0:16:07.680 --> 0:16:11.400 just keep a dog from over grooming or overlicking a 0:16:11.440 --> 0:16:15.280 wound site. But maybe even more importantly, wound licking while 0:16:15.320 --> 0:16:20.920 it removes some contaminants and microbes, it introduces others. The 0:16:20.960 --> 0:16:24.680 mouth is not sterile, so it's going to be delivering 0:16:25.000 --> 0:16:28.800 bacteria from the mouth cavity to the wound and this 0:16:28.840 --> 0:16:32.560 does come with genuine risks, especially if the animal's oral 0:16:32.600 --> 0:16:36.760 health is poor, or if it has mouth infections, or 0:16:36.800 --> 0:16:40.240 if the animal's immune system is compromised, or if the 0:16:40.280 --> 0:16:45.120 animal just has an oral microbiome that is more dangerous 0:16:45.160 --> 0:16:48.320 to cross link to open wounds. So you might imagine 0:16:48.320 --> 0:16:51.720 that this could be the case with carnivores. A carnivore 0:16:51.960 --> 0:16:55.120 licking its wounds, that might be a riskier behavior than 0:16:55.160 --> 0:16:58.720 a herbivore licking its wounds on average, but still a 0:16:58.720 --> 0:17:01.600 lot of carnivores do it, so the benefits still seem 0:17:01.640 --> 0:17:05.359 to outweigh the costs in nature. So if it comes 0:17:05.359 --> 0:17:08.000 with these dangers, you can, you know, maybe contaminate the 0:17:08.000 --> 0:17:10.359 wound with bacteria from the mouth. If it comes with 0:17:10.400 --> 0:17:13.199 these dangers, why does the behavior continue? Why does it 0:17:13.240 --> 0:17:16.400 persist in nature? It just seems like it's a case 0:17:16.440 --> 0:17:20.080 of trade offs, and on average, the wound looking instinct 0:17:20.400 --> 0:17:24.200 does more good than harm in the animals where it persists, 0:17:25.000 --> 0:17:27.439 it helps and it causes harm, and it does a 0:17:27.480 --> 0:17:30.080 little bit more of the former than the latter. So 0:17:30.119 --> 0:17:31.920 it's the evolutionary math works out. 0:17:32.119 --> 0:17:36.240 Yeah, does it allow the individual animal in question to 0:17:37.000 --> 0:17:40.000 live long enough to do more reproduction? Essentially, like it 0:17:40.080 --> 0:17:41.120 kind of boils down to. 0:17:41.080 --> 0:17:43.679 That, Yeah, Or if it just you've got a wound 0:17:43.680 --> 0:17:47.720 and it makes things worse forty percent of the time, 0:17:47.760 --> 0:17:50.520 but makes things better seventy percent of the time, I'll 0:17:50.560 --> 0:17:54.120 take that you know, you know odd, or I guess 0:17:53.920 --> 0:17:57.159 the math I just proposed didn't work out, but seventy 0:17:57.240 --> 0:18:00.840 thirty I guess yeah, I just I don't know what 0:18:00.880 --> 0:18:04.199 the real numbers are. But anyway, with the knowledge of 0:18:04.240 --> 0:18:06.399 germ theory and modern medicine, we don't have to go 0:18:06.480 --> 0:18:09.600 with this math. Fortunately, because by washing out a wound 0:18:09.640 --> 0:18:14.800 with clean water and soap and applying clean pharmaceutical antimicrobials 0:18:14.800 --> 0:18:17.520 to the wound site, you can basically get all of 0:18:17.560 --> 0:18:21.400 the benefits of wound looking with none of the risks. Now, 0:18:21.440 --> 0:18:25.080 another interesting thing about wound locking is that there are 0:18:25.280 --> 0:18:29.880 two different versions of this behavior. There's the main kind 0:18:29.880 --> 0:18:33.320 we've been talking about, which is self directed wound loocking 0:18:33.400 --> 0:18:37.520 licking your own cut or scrape. But there's also what's 0:18:37.560 --> 0:18:41.679 called communal wound looking, licking the wounds of others of 0:18:41.760 --> 0:18:45.720 your species. I found a good quick review of the 0:18:45.760 --> 0:18:49.119 research on communal wound looking in the background section of 0:18:49.160 --> 0:18:52.960 a paper called Licking their Wounds Social Response to Trauma 0:18:53.000 --> 0:18:57.120 by free ranging Bison. This is by Thomas Young, Kayleye. Thacker, 0:18:57.160 --> 0:19:00.480 and Christopher Lewis, published in the journal Ethology in twenty 0:19:00.520 --> 0:19:04.520 twenty three, and they talk about how communal wound looking 0:19:04.880 --> 0:19:09.720 has broadly the same hygienic and healing acceleration benefits as 0:19:09.760 --> 0:19:14.920 self directed licking, but with some interesting added factors. One 0:19:14.960 --> 0:19:18.120 is that if animals in a group lick the wounds 0:19:18.160 --> 0:19:22.400 of other animals, this allows the treatment of wound sites 0:19:22.440 --> 0:19:26.120 that the animals cannot reach with their own mouths. So 0:19:26.160 --> 0:19:28.400 this gets around the flexibility problem. 0:19:29.400 --> 0:19:32.080 Right, especially if you're dealing I mean, you could be 0:19:32.119 --> 0:19:34.560 dealing with human beings again, but especially if you're thinking 0:19:34.560 --> 0:19:37.160 about large herbivores. 0:19:37.240 --> 0:19:40.600 Yeah, yeah, But also this is interesting there could be 0:19:40.720 --> 0:19:45.800 secondary social benefits which are parallel to the benefits of 0:19:45.880 --> 0:19:51.080 social grooming. Young and co authors note that group wound 0:19:51.119 --> 0:19:54.800 looking might trigger a release of the hormone oxytocin and 0:19:54.880 --> 0:20:00.040 other associated neurotransmitters, which could help reduce the stress of 0:20:00.080 --> 0:20:04.280 animals after a traumatic incident and could help strengthen social 0:20:04.359 --> 0:20:10.200 bonds among group members. So oxytocin chemically counteracts the effects 0:20:10.280 --> 0:20:14.480 of the hormone cortisol or stress hormone, and is thus 0:20:14.680 --> 0:20:18.920 used internally to deactivate the body's stress response. This can 0:20:18.960 --> 0:20:22.879 be really useful because while the stress response stress hormones 0:20:23.400 --> 0:20:26.320 are good for you in an emergency, like if you 0:20:26.359 --> 0:20:28.720 are about to run or fight for your life, they 0:20:28.760 --> 0:20:31.760 quickly become a harmful burden on the body if you 0:20:31.800 --> 0:20:35.080 are not about to run or fight for your life, 0:20:35.240 --> 0:20:37.240 so you want to turn them off whenever you don't 0:20:37.240 --> 0:20:40.800 need them. I think we could all use that and 0:20:40.960 --> 0:20:43.359 find a way to turn the stress hormones off more often. 0:20:44.720 --> 0:20:51.960 Oxytocin is also importantly involved in forming social bonds between individuals. 0:20:52.080 --> 0:20:56.199 It plays some kind of role in complex cognitive and 0:20:56.240 --> 0:21:01.560 social effects like love, devotion, and loyalty. Though it's important 0:21:01.560 --> 0:21:04.800 to flag some caveats here because the role of oxytocin 0:21:04.880 --> 0:21:09.280 socially and cognitively I think sometimes it gets oversimplified. Oxytocin 0:21:09.400 --> 0:21:12.840 is not the only hormone that is involved in this stuff, 0:21:13.240 --> 0:21:16.239 and it's also not like an automatic love potion that 0:21:16.320 --> 0:21:19.480 just mechanistically makes us love people when it is released. 0:21:20.000 --> 0:21:24.680 Love and loyalty and related emotions are complex and multi causal, 0:21:25.160 --> 0:21:28.720 and even the chemical influences that feed into them are many. 0:21:30.000 --> 0:21:34.560 But oxytocin is important, and so it's if it is 0:21:34.680 --> 0:21:38.720 released by this communal wound looking behavior the same way 0:21:38.760 --> 0:21:42.520 that it is sometimes released during grooming behaviors that could 0:21:42.560 --> 0:21:45.920 signal that that communal wound looking plays some role in 0:21:46.119 --> 0:21:51.880 strengthening or regulating maintaining social bonds within a group. Communal 0:21:51.880 --> 0:21:55.840 wound looking has also been observed in rodents, in primates, 0:21:56.440 --> 0:21:59.080 and in this study by Young and co authors, it 0:21:59.119 --> 0:22:04.720 was observed in social ungulates, specifically bison in northwestern Canada, 0:22:05.160 --> 0:22:07.919 which had been shot with tranquilizer darts so that they 0:22:07.960 --> 0:22:11.760 could be tagged for tracking the author's right quote. The 0:22:11.840 --> 0:22:15.600 day after being darted, we observe three different adult bison 0:22:15.760 --> 0:22:19.840 lick the wounds of the two wounded bison. Both bison 0:22:19.960 --> 0:22:23.280 were less than three meters, were within less than three 0:22:23.320 --> 0:22:26.280 meters of each other during this time, and all of 0:22:26.320 --> 0:22:29.320 the observed wound looking occurred in less than ten minutes. 0:22:29.760 --> 0:22:33.439 Our observation provides an additional example of communal wound locking 0:22:33.760 --> 0:22:37.480 in free ranging mammals and extends it to a social ungulate. 0:22:37.760 --> 0:22:41.640 Benefits to bison of communal wound looking are perhaps largely social, 0:22:42.520 --> 0:22:45.359 and that kind of brings me back to thoughts about 0:22:45.359 --> 0:22:49.679 these stories of dogs licking humans wounds. You know, this 0:22:49.720 --> 0:22:52.159 is an even further thing where it's like a cross 0:22:52.280 --> 0:22:56.959 species wound looking behavior kind of makes me think that 0:22:56.960 --> 0:23:01.439 that is cross species wound looking, I doubt is something 0:23:01.480 --> 0:23:06.120 that is directly specifically an evolved adaptation, but probably more 0:23:06.160 --> 0:23:10.240 like a you know, a misapplication of a general wound 0:23:10.280 --> 0:23:14.320 licking impulse that's primarily probably focused on a dog's own 0:23:14.480 --> 0:23:16.760 kind or its own ancestors. 0:23:17.160 --> 0:23:17.440 Yeah. 0:23:17.680 --> 0:23:20.080 Yeah, And I guess that one of the things that 0:23:20.320 --> 0:23:23.000 potentially complicates all of this, or a least adds another dimension, 0:23:23.440 --> 0:23:26.840 because so many things in animal behavior they're they're not 0:23:27.359 --> 0:23:31.439 so cleanly defined by one category. Is that of course, 0:23:32.160 --> 0:23:34.200 I mean just looking at the dog, right. A dog 0:23:34.280 --> 0:23:37.040 will also lick you in the face when there's not 0:23:37.080 --> 0:23:39.560 a wound there, That's right. One of my friend's dogs 0:23:39.600 --> 0:23:42.720 routinely just licks my pants the whole time I'm over 0:23:42.760 --> 0:23:46.240 at his house, and I'm not sure exactly why. 0:23:46.640 --> 0:23:49.960 Yeah, so there could be multiple different motivations going on 0:23:50.040 --> 0:23:51.760 for that kind of licking. Like it could be a 0:23:52.480 --> 0:23:56.439 social grooming kind of thing. It's a social behavior that is, 0:23:57.240 --> 0:23:59.520 you know, to help dogs relate to each other and 0:23:59.560 --> 0:24:03.600 maintain their relationships, something about bonding. It could be a 0:24:04.040 --> 0:24:05.960 it could just be a you know, like taste and 0:24:06.000 --> 0:24:09.560 texture thing like a dog is you know, it likes 0:24:09.720 --> 0:24:13.199 something it's getting from this licking feeling or from the 0:24:13.240 --> 0:24:16.520 licking taste there. It might I wonder if dogs licking 0:24:16.640 --> 0:24:19.400 human wounds could just be because they're getting some salty there. 0:24:19.840 --> 0:24:22.000 I mean, yeah, all of these things are kind of 0:24:22.000 --> 0:24:25.120 in play with some topics related to the cat we're 0:24:25.119 --> 0:24:27.800 about to get into, because I didn't really I didn't 0:24:27.800 --> 0:24:31.320 specifically look at cat wound licking though, as we already mentioned, 0:24:31.320 --> 0:24:33.720 like they are a type of organism that does this, 0:24:33.840 --> 0:24:36.399 but I was looking at various other forms of social licking, 0:24:36.440 --> 0:24:38.159 and yeah, it's one of these areas where there are 0:24:38.160 --> 0:24:42.120 a number of different overlaps and some competing and potential 0:24:42.160 --> 0:24:45.199 potentially overlapping theories as to why they engage in it, 0:24:45.240 --> 0:24:46.720 And a lot of it does come down to like 0:24:46.800 --> 0:24:51.200 social activity, the release of potential release of hormones, and 0:24:51.240 --> 0:24:54.480 how it makes the individual cat feel to groom or 0:24:54.520 --> 0:24:58.520 be groomed. So moving on to cats, then, if you 0:24:58.640 --> 0:25:00.520 have ever lived with a cat, I know that they 0:25:00.560 --> 0:25:04.439 have various tactile ways to make their feelings known. You 0:25:04.480 --> 0:25:07.000 may receive the scratch, you may get the wet and 0:25:07.080 --> 0:25:12.000 nose boop, the rub the head butt, the making of biscuits. 0:25:12.080 --> 0:25:15.640 Of course, the coveted lap set. You may also find 0:25:15.680 --> 0:25:16.560 yourself licked. 0:25:17.600 --> 0:25:21.480 A connoisseur of pet affection may notice a textural difference 0:25:22.080 --> 0:25:25.239 in cat licks and dog licks. I find that the 0:25:25.280 --> 0:25:28.679 dog's tongue is somewhat softer. The cat's tongue is somewhat rougher. 0:25:29.560 --> 0:25:32.280 Yes, due to the papilla on the cat Tonguehich I'll 0:25:32.320 --> 0:25:36.800 get into. It's like it's essentially their comb. As you've observed, 0:25:36.800 --> 0:25:40.439 cats will rigorously groom themselves with their tongue, and the 0:25:40.480 --> 0:25:43.560 papilla on their tongue allows them to essentially, you know, 0:25:44.000 --> 0:25:46.200 they work like the again, the teeth of a comb. 0:25:47.160 --> 0:25:48.920 And that's why it's a little bit scratchy. And that's 0:25:48.920 --> 0:25:51.800 why being licked by a cat is often a ticklish affair, 0:25:52.600 --> 0:25:55.000 one that caused for a certain amount of what's going on? 0:25:55.119 --> 0:25:57.560 Why is it happening? Sort of reaction. 0:25:58.080 --> 0:26:00.400 When I think about the cat's tongue, I pretty much 0:26:00.440 --> 0:26:04.560 always think of the eighteenth century English poet Christopher Smart, 0:26:05.119 --> 0:26:08.200 who wrote I think some of the best cat poetry 0:26:08.200 --> 0:26:12.480 of all time, in a section known as for I 0:26:12.560 --> 0:26:15.280 will consider my cat Jeffrey after the first line in 0:26:15.320 --> 0:26:19.600 the section in his devotional Christian poem Jubilate Agno, meaning 0:26:19.680 --> 0:26:23.080 rejoice in the lamb. Smart wrote this when he was 0:26:23.119 --> 0:26:26.760 confined to a mental institution in London called Saint Luke's 0:26:26.760 --> 0:26:29.560 Hospital for Lunatics. This was roughly in the middle of 0:26:29.600 --> 0:26:32.520 the eighteenth century. I know I've brought this poem up 0:26:32.560 --> 0:26:34.640 on the show before at some point. 0:26:34.680 --> 0:26:36.879 Yeah, because I remember one line in particular. Now that 0:26:36.920 --> 0:26:38.200 I'm looking at it again. 0:26:38.320 --> 0:26:40.600 I just love it. It's too long to read in 0:26:40.680 --> 0:26:42.320 full here, but I love it so much. I have 0:26:42.400 --> 0:26:44.640 to mention the part leading up to the part about 0:26:44.640 --> 0:26:47.040 the tongue, but then also one other highlight from later. 0:26:47.800 --> 0:26:50.080 So the section leading up to the tongue line goes 0:26:50.119 --> 0:26:54.520 like this, He's celebrating all of He's just adoring his cat, 0:26:54.560 --> 0:26:58.720 Jeffrey's celebrating all of Jeffrey's virtues. And Smart writes, for 0:26:58.800 --> 0:27:01.440 he is the quickest to his of any creature, for 0:27:01.560 --> 0:27:04.159 he is tenacious of his point. For he is a 0:27:04.160 --> 0:27:07.680 mixture of gravity and waggery. For he knows that God 0:27:07.760 --> 0:27:10.760 is his savior. For there is nothing sweeter than his 0:27:10.840 --> 0:27:13.720 peace when at rest. For there is nothing brisker than 0:27:13.720 --> 0:27:16.439 his life when in motion, for he is of the 0:27:16.480 --> 0:27:19.919 Lord's poor, and so indeed is he called by benevolence 0:27:19.960 --> 0:27:24.359 perpetually poor Jeffrey. Poor Jeffrey. The rat has bit thy throat. 0:27:25.080 --> 0:27:27.240 For I bless the name of the Lord Jesus, that 0:27:27.320 --> 0:27:30.639 Jeffrey is better, for the divine spirit comes about his 0:27:30.720 --> 0:27:35.200 body to sustain it in complete cat. For his tongue 0:27:35.240 --> 0:27:38.480 is exceeding pure, so that it has in purity what 0:27:38.600 --> 0:27:39.920 it wants in music. 0:27:40.400 --> 0:27:40.920 Beautiful. 0:27:41.200 --> 0:27:44.040 It really is beautiful. And that last line, So that's 0:27:44.080 --> 0:27:47.000 the line about the tongue. It's exceeding pure, it has 0:27:47.080 --> 0:27:50.960 in purity what it wants in music. I don't know 0:27:51.000 --> 0:27:53.560 if there's a meaning there that is going past me 0:27:53.640 --> 0:27:57.119 through cultural context or beliefs about cats at the time, 0:27:57.600 --> 0:28:01.040 but my interpretation is cat mau is just as good 0:28:01.080 --> 0:28:04.320 as human mouth, even though cat mouth cannot talk. Cat 0:28:04.400 --> 0:28:07.200 licks better than or equal to human words. 0:28:08.119 --> 0:28:09.760 Yeah, yeah, I would. I would agree with that. Like, 0:28:09.960 --> 0:28:11.960 I'm not a huge fan of my cat licking me, 0:28:12.040 --> 0:28:17.879 but when she does, I do acknowledge that it. I mean, 0:28:17.920 --> 0:28:19.399 I don't want to overstate it and be like it 0:28:19.440 --> 0:28:21.399 is an act of love or whatever, but at the 0:28:21.480 --> 0:28:23.600 very least. It is a neutral act, and I know 0:28:23.680 --> 0:28:26.879 that I am in okay graces with the animal at 0:28:26.880 --> 0:28:30.000 the moment. That's what we go to go for in 0:28:30.040 --> 0:28:31.600 this household, sustaining neutrality. 0:28:32.560 --> 0:28:35.560 I think it's okay to call that love. You understand, 0:28:35.600 --> 0:28:38.440 you know, you understand the differences in cats and humans. 0:28:38.440 --> 0:28:40.719 But still there's there's something there that you know, you 0:28:40.760 --> 0:28:41.880 can make that metaphorical. 0:28:41.960 --> 0:28:44.400 Leave yeah, as long as yeah, I know, I'm calling 0:28:44.440 --> 0:28:45.520 it love, So it's fine. 0:28:46.120 --> 0:28:48.640 The one other passage I wanted to read here, this 0:28:48.720 --> 0:28:50.400 is from sort of the end of the section about 0:28:50.440 --> 0:28:54.200 Jeffrey Smart rites. For by stroking of him, I have 0:28:54.360 --> 0:28:59.000 found out electricity. For I perceived God's light about him, 0:28:59.000 --> 0:29:03.959 both wax and fire. For the electrical fire is the 0:29:04.000 --> 0:29:08.200 spiritual substance which God sends from Heaven to sustain the bodies, 0:29:08.240 --> 0:29:11.640 both of man and beast. For God has blessed him 0:29:11.640 --> 0:29:15.000 in the variety of his movements. For though he cannot fly, 0:29:15.200 --> 0:29:18.920 he is an excellent clamberer. For his motions upon the 0:29:18.920 --> 0:29:21.560 face of the earth are more than any other quadruped. 0:29:22.000 --> 0:29:25.080 For he can tread to all the measures upon the music. 0:29:25.520 --> 0:29:28.240 For he can swim for life or he Can. 0:29:28.080 --> 0:29:31.680 Creep, Joe, you will be delighted to know that for 0:29:31.880 --> 0:29:36.000 He Can Creep is the title of an episode of 0:29:36.000 --> 0:29:40.000 the latest season of Love, Death, and Robots, and it 0:29:40.080 --> 0:29:44.040 is about a poet and a sanitarium and his beloved 0:29:44.120 --> 0:29:50.240 cat named Jeffrey stands against the forces of darkness and 0:29:50.640 --> 0:29:51.400 it's rather good. 0:29:51.720 --> 0:29:53.920 I haven't seen that show, but really tempted to watch 0:29:53.960 --> 0:29:56.640 now because yeah, I love for my cat Jeffrey. 0:29:56.800 --> 0:30:01.200 Yet features the voice of Jim Broadman as Christopher the Poet. 0:30:02.760 --> 0:30:04.600 Well, there's other stuff I couldn't get to here, so 0:30:04.640 --> 0:30:07.200 I just recommend anybody who wants to go look up 0:30:07.480 --> 0:30:10.720 the four I will consider my cat Jeffrey section of 0:30:10.760 --> 0:30:13.800 the poem Jubilate Agno. You can find it online. 0:30:13.800 --> 0:30:19.760 It's great, excellent, excellent. You know, I recently watched part 0:30:19.760 --> 0:30:22.080 of a series started it watching it with my kid, 0:30:23.680 --> 0:30:28.520 titled Night of the Living Cat. It is a Japanese 0:30:28.560 --> 0:30:31.720 animated series based on a manga and Takashi mi k 0:30:33.080 --> 0:30:36.440 played a hand in it. But it's so far at 0:30:36.520 --> 0:30:40.960 least it's totally age appropriate. But it's super fun because 0:30:40.960 --> 0:30:43.560 it's obviously a parody of zombie and apocalypse films, except 0:30:43.600 --> 0:30:47.240 The whole idea is that cats carry some sort of 0:30:47.240 --> 0:30:49.520 a virus, and if they come into contact with you, 0:30:49.600 --> 0:30:52.680 and certainly if they lick you, you too will become 0:30:52.720 --> 0:30:55.360 a cat. And so the population of the planet is 0:30:55.400 --> 0:30:57.320 swiftly becoming a population of cats. 0:30:57.480 --> 0:30:58.120 Whoa. 0:30:58.280 --> 0:31:01.160 So that's very much an inversion of the Christopher Smart 0:31:01.160 --> 0:31:03.000 idea about the purity of the tongue. 0:31:03.280 --> 0:31:06.360 Well, the show is pretty fun and that it also 0:31:06.440 --> 0:31:09.600 plays with the fact that even though humans recognize that 0:31:10.360 --> 0:31:14.320 the cats are bringing their destruction, they also still love cats, 0:31:14.000 --> 0:31:17.840 and so they can't bring themselves to do violence against 0:31:17.840 --> 0:31:20.840 cats or anything of that nature. It's just like a 0:31:20.880 --> 0:31:24.120 heartbreaking affair. It's pretty fun though so far, so I'd 0:31:24.160 --> 0:31:37.600 like that premise. Yeah, all right, Well, getting back into licking. 0:31:37.880 --> 0:31:41.400 Licking is of course just one way that cats communicate 0:31:41.440 --> 0:31:44.960 and or get information about the world. They may lick 0:31:45.000 --> 0:31:49.480 your skin out of curiosity, if you particularly. Theories vary 0:31:49.520 --> 0:31:51.920 on all this, but one idea is that they might 0:31:52.000 --> 0:31:54.719 lick you because your skin is salty, or you have 0:31:54.760 --> 0:31:59.480 something on your skin that is interesting. And I'm not 0:31:59.480 --> 0:32:01.560 sure there's a firm answer on any of that, but 0:32:01.680 --> 0:32:04.840 it just may be part of the scenario. So if 0:32:04.840 --> 0:32:06.640 your cat is licking you and there doesn't seem to 0:32:06.640 --> 0:32:08.320 be any rhyme or reason, it could just be that 0:32:08.400 --> 0:32:11.960 where they're just like, oh, salty interesting, or oh lotion interesting. 0:32:12.360 --> 0:32:16.920 Of course, as with any domesticated or semi domesticated animal, 0:32:17.000 --> 0:32:20.240 depending on how you view cats, the relationship that we 0:32:20.360 --> 0:32:22.920 have with house cats is complicated by all of this, 0:32:23.080 --> 0:32:25.520 of course, and in some ways whatever we have going 0:32:25.520 --> 0:32:27.200 on with the cat is a perversion of what would 0:32:27.200 --> 0:32:31.000 occur in nature. So in some ways, the best way 0:32:31.000 --> 0:32:35.880 to understand what they're licking of us means we have 0:32:35.960 --> 0:32:38.080 to look at how they interact with other cats in 0:32:38.120 --> 0:32:42.719 their natural environment, So especially looking at colonies of cats 0:32:43.040 --> 0:32:45.880 where a number of cats have essentially come together or 0:32:46.600 --> 0:32:49.720 kind of aggregated in such a way that they don't 0:32:49.720 --> 0:32:51.720 have to worry so much about food, they're not competing 0:32:51.760 --> 0:32:54.240 with each other, and they will find some sort of stability. 0:32:54.280 --> 0:32:56.320 Doesn't mean they all get along with each other, though, 0:32:56.640 --> 0:32:59.360 because cats will have and I've seen this term used 0:32:59.400 --> 0:33:03.200 multiple times, they will have preferred associates. To be clear, 0:33:03.440 --> 0:33:07.360 they do not have friends, they have preferred associates, which 0:33:07.440 --> 0:33:09.640 which I like. It sounds like cat legal eese. 0:33:10.320 --> 0:33:12.600 Maybe I've just got film noir on the brain because 0:33:12.880 --> 0:33:14.880 of the stuff we've been doing on Weird House Cinema. 0:33:14.920 --> 0:33:19.320 But I'm thinking of like Humphrey Bogart's associates in the 0:33:19.360 --> 0:33:24.400 noir films, people that he's not exactly lovely with, but 0:33:24.560 --> 0:33:27.320 you know, they they sort of have a working relationship. 0:33:27.400 --> 0:33:31.680 They tolerate, into some sense, depend on each other. Yeah, 0:33:31.920 --> 0:33:37.800 so among preferred associates you encounter a number of different actions. 0:33:37.520 --> 0:33:41.280 There's something called alla rubbing. This is when they rub 0:33:41.280 --> 0:33:43.360 their bodies and tails against each other as a form 0:33:43.400 --> 0:33:46.200 of social bonding and communication. So I think everyone has 0:33:46.200 --> 0:33:49.880 seen an example of this and with cats and other cats, 0:33:49.920 --> 0:33:52.840 but also anytime they rub against especially if they rub 0:33:52.840 --> 0:33:56.959 against your legs, this is seen as an extinct as 0:33:57.080 --> 0:33:59.960 an extension of this behavior. Now I'm not sure about 0:34:00.040 --> 0:34:03.760 feet because speaking mainly from my experience, rubbing against my 0:34:03.840 --> 0:34:07.920 feet often quickly devolves into play and play biting of 0:34:08.000 --> 0:34:11.759 my feet, and of course levels of play are going 0:34:11.840 --> 0:34:14.680 to occur, especially in younger cats, but even in older cats, 0:34:14.680 --> 0:34:17.840 and then indoor cats is kind of a forever kitten 0:34:17.880 --> 0:34:23.560 scenario by some estimates. So again, another example where you 0:34:23.560 --> 0:34:28.279 can't just talk about the social behavior among preferred associates, 0:34:28.320 --> 0:34:30.400 because it could descend into play at any point, and 0:34:30.440 --> 0:34:31.760 that's another factor in everything. 0:34:32.400 --> 0:34:32.640 I know. 0:34:32.760 --> 0:34:35.239 This is asking you to get inside the mind of 0:34:35.280 --> 0:34:38.760 a cat, which may be impossible. But you've talked before 0:34:38.800 --> 0:34:42.040 about your cat having a habit of attacking your feet 0:34:42.320 --> 0:34:45.880 out from underneath furniture. Do you get the sense that 0:34:45.920 --> 0:34:49.680 your cat in the moment is thinking of your feet 0:34:49.719 --> 0:34:53.319 as part of your body or are the feet just 0:34:53.640 --> 0:34:56.399 something that's moving? Does that make sense? 0:34:57.480 --> 0:35:00.720 That's a complicated question and one that I've I've heard 0:35:01.320 --> 0:35:04.000 more broadly explored a lot of times just talking about 0:35:04.000 --> 0:35:07.600 what do cats think humans are? And I've heard the 0:35:07.719 --> 0:35:10.000 argument that, you know, they think that we're other cats, 0:35:10.520 --> 0:35:12.800 and if they think that there were other cat, other cats, 0:35:12.840 --> 0:35:15.080 then it makes sense to engage in play with us. 0:35:15.480 --> 0:35:18.160 Play generally takes the form of fake fighting. 0:35:18.840 --> 0:35:19.040 I know. 0:35:19.080 --> 0:35:21.040 Another thing that my cat will do is come up 0:35:21.080 --> 0:35:24.040 next to my foot, my sockt foot, PLoP down next 0:35:24.080 --> 0:35:27.359 to that foot, way too close to my foot, as 0:35:27.360 --> 0:35:30.719 if inviting me to rub against her. And even if 0:35:30.719 --> 0:35:33.520 I don't rub against her, she may just start attacking 0:35:33.520 --> 0:35:37.680 my foot. So so like that's one way, But then 0:35:37.719 --> 0:35:42.879 there's there's also the idea that cats see us as 0:35:43.280 --> 0:35:47.360 part of their environment as well, so like we we 0:35:47.680 --> 0:35:50.560 also have sort of like a deep personified status to 0:35:50.600 --> 0:35:53.360 some degree where we are just part of the place 0:35:53.440 --> 0:35:56.560 that they are comfortable with. And I mean, we can 0:35:56.600 --> 0:35:59.880 certainly understand that when they use us as a heated 0:36:00.239 --> 0:36:01.960 bed and just want to sit on this all the 0:36:01.960 --> 0:36:03.240 time during the colder months. 0:36:04.120 --> 0:36:05.680 Are we warm moving furniture? 0:36:06.040 --> 0:36:09.560 Yeah, So I don't know. I'm willing to bet there's 0:36:09.560 --> 0:36:11.759 maybe a little bit of both of these scenarios going on. 0:36:11.960 --> 0:36:13.880 And you know, the cat is going to have a 0:36:15.000 --> 0:36:17.799 you know, probably from our standpoint, a perplexing understanding of 0:36:17.840 --> 0:36:20.600 other beings, Like they're not going to perceive other beings 0:36:20.600 --> 0:36:23.720 the same way we do. We're going to and it's 0:36:23.760 --> 0:36:27.240 probably a lot easier to understand their perception of definite 0:36:27.280 --> 0:36:29.719 prey or predator status organisms. 0:36:30.120 --> 0:36:32.279 Maybe it was not a meaningful question, No. 0:36:32.160 --> 0:36:33.920 No, I think it's a fascinating quest when I think 0:36:33.920 --> 0:36:37.880 about all the time I lock eyes with this creature 0:36:37.880 --> 0:36:40.000 across the room, and I'm like, what does she think 0:36:40.000 --> 0:36:40.399 I am? 0:36:41.080 --> 0:36:41.160 Like? 0:36:41.200 --> 0:36:44.240 What am I to her? And indeed, then I turn around. 0:36:44.239 --> 0:36:45.799 What is she to me? I don't know. These are 0:36:45.800 --> 0:36:49.320 difficult questions to ask. But coming back to alo rubbing, 0:36:50.000 --> 0:36:52.920 there is this seeming we might think of it as 0:36:52.920 --> 0:36:58.080 an emotional context to it as well. I was reading 0:36:59.320 --> 0:37:03.640 two thousand five Understanding Feline Signaling and Social Interactions. This 0:37:03.760 --> 0:37:06.680 is from the proceedings of the North American Veterinary Conference 0:37:07.120 --> 0:37:11.439 by Sharon L. Crowell Davis, and she pointed out that 0:37:11.680 --> 0:37:14.080 in many ways this just is this rubbing of cats 0:37:14.120 --> 0:37:16.200 against each other, and indeed a rubbing of a cat 0:37:16.200 --> 0:37:18.800 against your leg. It's in many ways like a hug, 0:37:19.200 --> 0:37:22.480 like it's comforting to them in the same way that 0:37:22.760 --> 0:37:25.400 like other activities they do seem to be based purely 0:37:25.440 --> 0:37:28.600 on comfort. Like for instance, cats will often be in 0:37:28.640 --> 0:37:32.399 physical contact with each other while they are sleeping and 0:37:32.760 --> 0:37:36.680 during the during cold months or cold environments, and again 0:37:36.800 --> 0:37:39.360 cold by a cat standards, which is a little different 0:37:39.360 --> 0:37:42.680 than human standards. It makes sense, right while they're sharing 0:37:42.680 --> 0:37:45.600 each other's body heat. But they'll also do it even 0:37:45.719 --> 0:37:48.439 if thermoregulation doesn't seem to be an issue. If it's 0:37:48.480 --> 0:37:51.600 you know, hotter, warmer, and so forth, it may be 0:37:51.760 --> 0:37:53.880 that they do these things, you know, just because it 0:37:53.960 --> 0:37:58.400 is comforting to do them, and that gets to straight 0:37:58.480 --> 0:38:01.480 up grooming as well. In the of licking a fur, 0:38:03.280 --> 0:38:06.160 this is something that may be acquired and when they're 0:38:06.200 --> 0:38:11.120 kittens it's comforting behavior. It might also be a way 0:38:11.160 --> 0:38:13.600 to mark others. As we'll discuss a little bit more. 0:38:13.640 --> 0:38:17.000 And as Carole Davis points out, humans have this terrible 0:38:17.040 --> 0:38:19.279 sense of smell. We just can't we can't smell at all, 0:38:19.400 --> 0:38:23.400 We've discussed as many times before, at anywhere close to 0:38:23.440 --> 0:38:26.080 the same level as even a cat, and certainly not 0:38:26.120 --> 0:38:30.480 a dog. So just it becomes very difficult for us 0:38:30.520 --> 0:38:34.480 to understand or comprehend the olfactory lives of animals like this, 0:38:35.080 --> 0:38:37.719 Like not only not just like a chemical understand like 0:38:37.719 --> 0:38:39.640 we can sort of break down the chemical understanding of 0:38:39.760 --> 0:38:42.840 chemical markers, but in terms of like translating that into 0:38:42.840 --> 0:38:46.240 our like sort of larger understanding of how animals operate 0:38:46.280 --> 0:38:47.960 in the world, it can be challenging. 0:38:48.200 --> 0:38:51.920 Yeah, they have an information rich relationship to the environment 0:38:52.000 --> 0:38:55.239 on a dimension that where we come nowhere close. 0:38:55.600 --> 0:38:58.280 Right, But getting back to where we're talking about with dogs, 0:38:58.440 --> 0:39:02.239 with cats too, licking and grooming or soothing behaviors, it 0:39:02.320 --> 0:39:06.439 stirs the release of endorphins. They may lick themselves, other 0:39:06.600 --> 0:39:10.719 cats or humans, or also materials in the home, and 0:39:11.320 --> 0:39:14.600 this can certainly spill over into excessive licking that may 0:39:14.600 --> 0:39:19.799 be a sign of stress or some other situation, but 0:39:19.920 --> 0:39:23.880 in general, it's like this is a calming action that 0:39:23.920 --> 0:39:25.120 they can partake of. 0:39:26.800 --> 0:39:27.000 Now. 0:39:27.040 --> 0:39:30.480 On top of that, of course, cats are famous for 0:39:31.080 --> 0:39:35.360 their use of self licking to fastidiously clean their own bodies, 0:39:35.800 --> 0:39:39.000 a self grooming process that takes up a substantial portion 0:39:39.200 --> 0:39:42.759 of their waking hours. I've seen different estimates on that 0:39:42.920 --> 0:39:45.319 this mostly I've seen an estimate of between thirty and 0:39:45.400 --> 0:39:48.760 forty percent of their waking hours, and this can amount 0:39:48.800 --> 0:39:52.920 to something like five hours apparently of just endless grooming. 0:39:53.880 --> 0:39:56.520 Cat owners will have noticed this, especially if your cat 0:39:57.040 --> 0:39:59.680 does want to treat you like a couch and then 0:39:59.840 --> 0:40:01.759 is like, hey, I'm not just going to sit here 0:40:01.760 --> 0:40:04.720 and watch television with you, I'm also going to clean myself. 0:40:04.760 --> 0:40:06.520 And then you're like, I don't want this anymore, and 0:40:06.600 --> 0:40:09.040 you have to push them off or gently push them off, 0:40:10.239 --> 0:40:12.520 or maybe you can put up with it. I find 0:40:12.560 --> 0:40:14.879 it a little hard to put up with, but but yeah, 0:40:14.920 --> 0:40:17.759 I've also seen like eight percent estimates. But anyway you 0:40:17.800 --> 0:40:20.160 cut it, they spend a lot of time self grooming, 0:40:21.160 --> 0:40:25.120 looking after their fur, cleaning it. And as I mentioned earlier, 0:40:25.760 --> 0:40:27.760 part of it is, you know, using those little barbs 0:40:27.760 --> 0:40:31.040 in their tongue, the sandpaper of their tongue to physically 0:40:31.040 --> 0:40:35.000 clean their furs. There's a little backward facing barbs and 0:40:35.520 --> 0:40:39.120 helps remove like little particles from their fur, kind of 0:40:39.120 --> 0:40:41.080 getting back to the womb cleaning that we were talking 0:40:41.080 --> 0:40:41.760 about earlier. 0:40:41.960 --> 0:40:42.919 Yeah. Yeah. 0:40:43.080 --> 0:40:45.439 On top of just the mechanical cleaning of their fur, 0:40:45.840 --> 0:40:48.760 self grooming also enables them to spread natural oils across 0:40:48.800 --> 0:40:53.880 their coat, helps keep it clean, waterproof and insulated. Also, 0:40:54.200 --> 0:40:57.520 as the saliva evaporates, it can also help cool them 0:40:57.560 --> 0:41:00.440 down as a means of thermoregulation. So that's seems to 0:41:00.440 --> 0:41:02.799 be in play as well. And then of course the 0:41:02.880 --> 0:41:06.640 act itself is self soothing. They are in there. You 0:41:06.680 --> 0:41:10.319 could almost say happy place if they are self grooming. Now, 0:41:10.360 --> 0:41:12.960 when it comes back to the human question, I did 0:41:12.960 --> 0:41:16.160 find a nice little explainer article that tackles this and 0:41:16.160 --> 0:41:18.000 covers some of the ground we've already discussed. This was 0:41:18.000 --> 0:41:20.520 for BBC Science Focus from I think a couple of 0:41:20.560 --> 0:41:24.880 years ago by Thomas Ling, and he basically broke it 0:41:24.920 --> 0:41:28.800 down into three different theories. The trust theory that they're 0:41:28.880 --> 0:41:31.400 making a display of trust towards you. My cat is 0:41:31.440 --> 0:41:34.200 licking me because they are saying you, I trust you 0:41:34.239 --> 0:41:38.319 are good, You are a preferred associate. Then there's the 0:41:38.320 --> 0:41:42.640 biochemical theory that there's something about your taste that's interesting, okay, 0:41:43.120 --> 0:41:45.399 salt your lotion or what have you. And then there's 0:41:45.400 --> 0:41:47.839 the possession play theory, and this is that they are 0:41:47.880 --> 0:41:50.520 marking you as their own. They're saying like, this person 0:41:50.600 --> 0:41:54.319 is my territory, this person is my property. And so 0:41:54.440 --> 0:41:57.320 going through each of these, starting with the trust theory, 0:41:57.400 --> 0:42:01.959 this is I think relatable to the oligrooming scenario, which 0:42:02.040 --> 0:42:05.600 means at best or a preferred affiliate. This should not 0:42:05.640 --> 0:42:08.640 be confused with love. If we're talking, you know, purely 0:42:08.719 --> 0:42:11.960 scientifically about the scenario. Again, we humans can call it love, 0:42:11.960 --> 0:42:14.719 but maybe just understand that in the literature they're not 0:42:14.760 --> 0:42:15.360 going to call it that. 0:42:16.640 --> 0:42:17.399 But yeah. 0:42:17.440 --> 0:42:20.880 Studies have shown though that any supposed trust bond that 0:42:20.920 --> 0:42:25.080 a cat is associating with a human, it doesn't necessarily 0:42:25.120 --> 0:42:28.200 mean it's absolute. So cats tend to be pretty solitary 0:42:28.320 --> 0:42:32.160 in many cases, and in studies they found that they 0:42:32.239 --> 0:42:35.319 get along well with strangers almost just as well or 0:42:35.360 --> 0:42:38.200 as just as well as they would with other humans, 0:42:38.239 --> 0:42:41.279 which cat owners I think sometimes observe this because in 0:42:41.320 --> 0:42:45.000 our closed environments where we think about, oh, the cat, 0:42:45.239 --> 0:42:47.320 she's so social, she loves us so much, she just 0:42:47.360 --> 0:42:49.399 wants to be around us. And I'm not discounting any 0:42:49.440 --> 0:42:52.120 of the social needs of cats, but it can also 0:42:52.160 --> 0:42:54.120 be a little bit alarming when a stranger comes over 0:42:54.160 --> 0:42:56.080 and it's like, cat's right in their lap and you're like, 0:42:56.160 --> 0:42:57.600 you want to be like, you don't know that person 0:42:57.640 --> 0:43:02.960 at all. Why weren't you said, in my lap? So, yeah, 0:43:03.200 --> 0:43:07.120 that's one caveat to the trust theory. I think we've 0:43:07.160 --> 0:43:11.200 hit the biochemical theory pretty well, and then the possession 0:43:11.200 --> 0:43:13.680 play theory basically comes down to the idea that the 0:43:13.719 --> 0:43:16.960 cat's own smell is the most important thing to it 0:43:17.719 --> 0:43:21.000 in terms of its olfactory world, Like, it wants to 0:43:21.000 --> 0:43:23.680 make sure it smells like itself, so it will lick 0:43:23.719 --> 0:43:26.440 away any foreign smells in order to order to champion 0:43:26.520 --> 0:43:29.080 and establish its own smell, and there may be some 0:43:29.320 --> 0:43:31.839 level of territory marking when they lick or rub their 0:43:31.840 --> 0:43:37.759 faces against humans, certainly like the face rubbing, which can 0:43:37.840 --> 0:43:40.080 lead to licking or follow licking. You know, you never 0:43:40.080 --> 0:43:42.120 know how it's going to go. You know. 0:43:42.200 --> 0:43:44.839 I just had the thought that I wish I'd thought 0:43:44.880 --> 0:43:47.359 of this before we recorded, so I could look it up. 0:43:47.400 --> 0:43:51.200 But while I'm aware of lots of stories from legends 0:43:51.239 --> 0:43:55.359 where a dog licks a human's wounds, I can't think 0:43:55.400 --> 0:43:58.320 of anywhere a cat licks a human's wounds. Cat licks, 0:43:59.000 --> 0:44:02.560 or at least not in anonical literature that I know of, wound. 0:44:02.280 --> 0:44:06.040 Related Yeah, that's interesting. Well, maybe we'll come back to that. 0:44:06.400 --> 0:44:17.520 Yeah, all right. 0:44:17.600 --> 0:44:20.160 To close out this episode, I would like to talk 0:44:20.200 --> 0:44:23.320 a little bit about eye licking. In the last episode, 0:44:23.400 --> 0:44:25.919 we discussed the idea of eye licking as it fits 0:44:25.920 --> 0:44:30.560 into the magical and mythic concepts of the ancient Egyptians. Naturally, 0:44:30.600 --> 0:44:33.120 a lot of social grooming animals will lick each other 0:44:33.200 --> 0:44:35.400 in the face and in the eye. Come back to 0:44:35.400 --> 0:44:38.120 a couple of examples of that, but I wanted to 0:44:38.160 --> 0:44:40.880 touch on a couple of examples of animals that definitely 0:44:40.920 --> 0:44:42.480 lick their own eyeballs. 0:44:43.200 --> 0:44:44.239 Oh this is good. 0:44:44.440 --> 0:44:47.800 Yeah, And of course it's interesting to us humans because 0:44:47.880 --> 0:44:51.400 most humans cannot do this. To be sure, there are 0:44:51.360 --> 0:44:56.800 way most most My initial thought was, and I like 0:44:56.880 --> 0:44:59.080 my original original draft of the notes, as I was 0:44:59.160 --> 0:45:00.600 kind of putting my thoughts to, I was like, well, 0:45:00.640 --> 0:45:02.360 humans can't look their own eyes, so of course we 0:45:02.440 --> 0:45:04.600 find this interesting. But then I dared to look a 0:45:04.640 --> 0:45:10.160 little closer, and there are certain individuals who can, by 0:45:10.239 --> 0:45:13.960 some definitions, lick their own eyeball. WHOA like, it's going 0:45:14.040 --> 0:45:18.239 to come down to a few different measurements. So you know, 0:45:18.320 --> 0:45:20.880 facial spacing certainly, and you know there's a fair amount 0:45:20.880 --> 0:45:24.080 of variety there, but tongue size is the big one. 0:45:24.760 --> 0:45:27.760 I was looking around, and I believe the average human 0:45:27.800 --> 0:45:30.720 tongue link is between three and three point three inches. 0:45:31.719 --> 0:45:36.560 But you have certain individuals who have verified or unverified 0:45:36.560 --> 0:45:41.480 claims for almost four inch tongues. And then there are 0:45:41.800 --> 0:45:45.080 at least claims and I don't know, maybe not certified, 0:45:45.120 --> 0:45:48.560 but to my eye eyes convincing arguments for four inch tongues. 0:45:49.719 --> 0:45:53.480 One in particular I was looking at, again not verified 0:45:53.719 --> 0:45:57.520 by Guinness as far as I understand, but one Adrian 0:45:57.680 --> 0:46:02.040 Lewis of the United Dates. You can look her up 0:46:02.080 --> 0:46:04.000 because she was kind of like she appeared on various 0:46:04.040 --> 0:46:06.960 news programs and like did social media and YouTube videos. 0:46:07.520 --> 0:46:11.560 But she could stick out her tongue, which is allegedly 0:46:11.600 --> 0:46:15.160 four inches long, and then using her finger, guide the 0:46:15.239 --> 0:46:19.319 tongue up until it I think comes in contact with 0:46:19.360 --> 0:46:22.040 the eye, or perhaps could come in contact with the eye. 0:46:22.800 --> 0:46:26.400 I'm speechless, I like you assume, would have said no 0:46:26.560 --> 0:46:29.480 human can lick their own eye. This is if this 0:46:29.560 --> 0:46:31.000 is true, it's flabbergasting to me. 0:46:31.160 --> 0:46:35.560 Yeah, so it seems entirely possible that some humans can 0:46:36.120 --> 0:46:38.879 bring their tongue into contact with their eye, if not 0:46:39.400 --> 0:46:41.799 lick it in the same way that you know, an 0:46:41.800 --> 0:46:45.680 animal with a long tongue can't, like as well to 0:46:45.680 --> 0:46:47.320 get into in a bit like a giraffe and a 0:46:47.400 --> 0:46:49.880 a copy can do this like they can without a 0:46:49.920 --> 0:46:52.200 doubt lick their own tongue. Humans might have to have 0:46:52.239 --> 0:46:55.640 a little help, and therefore, you know, it's very hard 0:46:55.640 --> 0:46:58.239 to argue that there's any practical application for this. 0:46:58.719 --> 0:47:01.279 Yeah, not a doctor, but I would not recommend it 0:47:01.480 --> 0:47:04.520 for the same base reasons why there are downsides to 0:47:04.560 --> 0:47:07.640 licking your wounds. You know, you don't want to introduce bacteria. 0:47:07.800 --> 0:47:10.080 The mouth is a bacteria rich environment. You don't want 0:47:10.080 --> 0:47:13.600 to introduce microbes into a different place in the body 0:47:13.640 --> 0:47:14.480 when you don't have to. 0:47:15.080 --> 0:47:18.439 Yeah, yeah, So I'll come back to the mammal world 0:47:18.520 --> 0:47:20.640 real quickly because I have less to say about the 0:47:20.680 --> 0:47:23.000 mammal world, because the ocopy and the giraffe are great 0:47:23.000 --> 0:47:28.600 examples of related organisms. They both self groom via tongue licking, 0:47:28.719 --> 0:47:32.239 including licking of their own face, and they may lick 0:47:32.280 --> 0:47:36.040 their eyes in the process. They also lick each other 0:47:36.160 --> 0:47:39.840 during courtship. But the best example, the most exciting example 0:47:39.960 --> 0:47:43.640 of an animal licking its own eyes, you'll find this 0:47:43.800 --> 0:47:49.359 with geckos. Geckos or of course, reptiles of the suborder Gekkota, 0:47:50.000 --> 0:47:53.400 of which there are at least fifteen hundred known species. 0:47:53.440 --> 0:47:57.040 There are a lot of geckos out there. All geckos 0:47:57.440 --> 0:48:01.800 can and do lick their own eyeball, and the main 0:48:01.960 --> 0:48:04.840 reason for their doing so, again, it's not just to 0:48:04.880 --> 0:48:07.840 show off on social media. They do it to clean 0:48:07.880 --> 0:48:10.960 their eyes and remove debris from their eyes, such as 0:48:10.960 --> 0:48:14.840 little grains of sand, particles, and so forth. Some geckos, however, 0:48:14.920 --> 0:48:17.640 would seem to depend on this ability much more than others, 0:48:19.200 --> 0:48:23.480 as discussed by herpetologist Aaron M. Bauer in the book Geckos, 0:48:23.520 --> 0:48:28.920 The Animal Answered Guide. All geckos have eyelids, but if 0:48:28.920 --> 0:48:32.640 you read some descriptions of the scenario, will say, you know, 0:48:32.719 --> 0:48:35.440 a lot of geckos don't have islids. All geckos have eyelids, 0:48:35.719 --> 0:48:41.799 but only the thirty species of the u Blephylaridae geckos 0:48:42.120 --> 0:48:45.920 can move those eyelids. So it's one thing to have eyelids, 0:48:45.960 --> 0:48:47.760 but can you actually make them. 0:48:47.600 --> 0:48:48.200 Go up and down? 0:48:48.480 --> 0:48:56.919 Oh? Okay, interesting, So the Ublephalaridae geckos, they close their 0:48:57.000 --> 0:49:00.520 eyes and blink, much like we do. The gecko that 0:49:00.640 --> 0:49:04.880 my child has, a leopard gecko, is one of these geckos. 0:49:06.360 --> 0:49:09.600 So you know, this gecko can blink his little eyes. 0:49:10.120 --> 0:49:12.759 And I'm not sure that I've actually observed him licking 0:49:12.840 --> 0:49:15.359 his own eyes, but according to the literature, he can 0:49:15.520 --> 0:49:17.560 and does do so. I just I don't watch him 0:49:17.600 --> 0:49:19.040 all the time. I don't know what he's up to 0:49:19.160 --> 0:49:19.799 most of the day. 0:49:21.360 --> 0:49:22.800 Does the cat watch him? 0:49:23.080 --> 0:49:25.960 No, they don't interact. We don't want to encourage that anyway. 0:49:26.239 --> 0:49:30.560 They're in their own little worlds, you know. Though one's 0:49:30.640 --> 0:49:32.840 name is Waffles and the other's name is mochi, so 0:49:32.840 --> 0:49:36.880 they're kind they're kind of siblings in that regard. So anyway, 0:49:36.880 --> 0:49:42.799 we've discussed the blithelarid geckos. The non eu blifferid geckos 0:49:43.160 --> 0:49:46.359 cannot move their eyelids. They have a structure called a 0:49:46.440 --> 0:49:49.880 spectacle or brill that covers the eye and it protects 0:49:49.920 --> 0:49:54.280 it from abrasian and dryness. Bauer describes it as derived 0:49:54.280 --> 0:49:57.360 from a transparent lower eyelid that has become fused with 0:49:57.440 --> 0:50:01.720 the upper eyelid, so a trans and disc positioned directly 0:50:01.800 --> 0:50:05.759 over the eye, and it's it's very much you know, 0:50:05.760 --> 0:50:09.040 it's sometimes described as being like a scale. And indeed 0:50:09.120 --> 0:50:11.600 it is part of the gecko's skin. So when the 0:50:11.719 --> 0:50:15.239 gecko sheds its skin, which it will eventually eat. That's 0:50:15.239 --> 0:50:17.000 one of the magical things of having a pet gecko 0:50:17.120 --> 0:50:20.680 is when he goes into his hide to shed, he's 0:50:20.719 --> 0:50:22.120 going to clean all that up. He's not going to 0:50:22.200 --> 0:50:24.600 let any of that god of waste. But when he 0:50:24.640 --> 0:50:28.000 does shed, that eyelid is going to come off with it. 0:50:28.920 --> 0:50:30.840 I believe it becomes like you can tell, it becomes 0:50:30.880 --> 0:50:33.759 like kind of translucent, or you know, not translucent, becomes 0:50:33.840 --> 0:50:36.360 kind of like gray. Perhaps before it comes off Wow 0:50:37.280 --> 0:50:40.960 delicious now. Additionally, some of these geckos also have eyelid 0:50:41.239 --> 0:50:46.279 like structures called extra briller fringes that partially cover the 0:50:46.360 --> 0:50:49.320 upper portion of the eye and can be partially raised 0:50:49.320 --> 0:50:52.880 and lower, but they're not fold it's either way. The 0:50:52.920 --> 0:50:56.200 main function of self eyelid licking is to keep things 0:50:56.239 --> 0:51:00.680 clean and clear. However, they'll also just lick their eyes 0:51:00.680 --> 0:51:03.200 and faces to drink water droplets off their face. If 0:51:03.200 --> 0:51:05.960 they have water on there, why not, you know, free drink. 0:51:06.640 --> 0:51:09.920 They've also been observed licking their own face after eating 0:51:10.040 --> 0:51:14.880 or running, basically some sort of strenuous activity, but the 0:51:14.960 --> 0:51:19.280 reason for this isn't entirely understood. So in eating, of course, 0:51:19.640 --> 0:51:23.120 bear in mind we're talking about geckos. They are little predators. 0:51:23.120 --> 0:51:25.840 They are eating live prey, so that there's an endurance 0:51:25.880 --> 0:51:29.080 aspect to that as well. Elsewhere in the book, Bauer 0:51:29.200 --> 0:51:33.040 notes that geckos often lick one another during courtship, and 0:51:33.200 --> 0:51:38.040 this is likely both tactile and chemical communication, with molecules 0:51:38.040 --> 0:51:42.640 on the tongue transferred to their vomeroonasal organ to then 0:51:42.680 --> 0:51:44.760 crunch the data about potential mates. 0:51:45.000 --> 0:51:47.759 Oh coming back to like the like the snakes. Yeah, yeah, 0:51:47.840 --> 0:51:48.839 the Jacobson's organ. 0:51:49.320 --> 0:51:49.520 Yeah. 0:51:49.560 --> 0:51:51.560 So if you have a gecko out there, you know, 0:51:52.040 --> 0:51:54.960 to watch them a little extra in the next couple 0:51:54.960 --> 0:51:58.680 of days. See, first of all, recall what sort of 0:51:58.760 --> 0:52:01.880 gecko you have, and see what sort of eye licking 0:52:01.920 --> 0:52:04.600 us up to. And if you can lick your own eyeball, 0:52:05.120 --> 0:52:10.000 don't do it. For starters. I encountered similar things looking 0:52:10.080 --> 0:52:13.920 into this, the idea of humans locking eyeballs, because for 0:52:13.560 --> 0:52:16.520 a subset of the human population, there is a certain 0:52:16.560 --> 0:52:23.239 eroticism to the licking of another human beings eye balls. Yeah, 0:52:23.280 --> 0:52:25.720 but you know, I mean, there's there's room for everything. 0:52:25.760 --> 0:52:27.040 I'm not going to shame anybody, but. 0:52:27.080 --> 0:52:28.560 This is judging. I'm just surprised. 0:52:28.640 --> 0:52:32.000 But this is not recommended by health experts. It's it 0:52:32.080 --> 0:52:34.960 kind of comes back to the dog looking a wound scenario. 0:52:35.040 --> 0:52:38.960 It's like, yeah, we have better ways to attend to 0:52:38.960 --> 0:52:43.120 the cleanliness of our eyes. So no need to have 0:52:43.239 --> 0:52:46.759 your eyes licked by even you know, even a trusted lover. 0:52:47.640 --> 0:52:50.719 But if you were a get go, I mean, go 0:52:50.840 --> 0:52:51.120 at it. 0:52:51.120 --> 0:52:51.960 It's your way of life. 0:52:52.640 --> 0:52:54.160 All right. We're going to go and close the book there, 0:52:54.160 --> 0:52:56.719 but we will be back so tune in for more 0:52:56.719 --> 0:52:58.560 episodes in the future. Just to remind it of the 0:52:58.560 --> 0:53:00.880 Stuff to Blow Your Mind is primary science and culture 0:53:00.920 --> 0:53:04.320 podcasts with core episodes and Tuesdays and Thursdays. On Wednesdays 0:53:04.360 --> 0:53:06.920 we do a short form episode, and on Fridays we 0:53:06.960 --> 0:53:09.239 set aside most serious concerns to just talk about a 0:53:09.280 --> 0:53:10.960 weird film on Weird House Cinema. 0:53:11.360 --> 0:53:15.080 Huge thanks as always to our excellent audio producer JJ Posway. 0:53:15.120 --> 0:53:16.640 If you would like to get in touch with us 0:53:16.719 --> 0:53:19.200 with feedback on this episode or any other, to suggest 0:53:19.200 --> 0:53:21.280 a topic for the future, or just to say hello, 0:53:21.680 --> 0:53:24.359 you can email us at contact at stuff to Blow 0:53:24.360 --> 0:53:32.359 your Mind dot com. 0:53:32.480 --> 0:53:35.440 Stuff to Blow Your Mind is production of iHeartRadio. For 0:53:35.520 --> 0:53:38.320 more podcasts from my heart Radio, visit the iHeartRadio app, 0:53:38.480 --> 0:53:56.400 Apple Podcasts, or wherever you listen to your favorite shows.